U.S. patent application number 10/866341 was filed with the patent office on 2005-07-14 for electronic component manufacturing apparatus, electronic component manufacturing method, and electronic component.
This patent application is currently assigned to KABUSHIKI KAISHA TOSHIBA. Invention is credited to Aoki, Hideo, Takubo, Chiaki, Yamaguchi, Naoko.
Application Number | 20050153249 10/866341 |
Document ID | / |
Family ID | 34737220 |
Filed Date | 2005-07-14 |
United States Patent
Application |
20050153249 |
Kind Code |
A1 |
Yamaguchi, Naoko ; et
al. |
July 14, 2005 |
Electronic component manufacturing apparatus, electronic component
manufacturing method, and electronic component
Abstract
There are provided a metal particulate spraying step to spray
metal particulates over a substrate having an insulating pattern
formed of thermosetting resin, a heating step to heat and dissolve
the resin pattern and fix the metal particulates on the resin
pattern, and a metal particulate eliminating step to eliminate
metal particulates attached on the surface of the substrate
excluding the resin pattern.
Inventors: |
Yamaguchi, Naoko;
(Yokohama-shi, JP) ; Aoki, Hideo; (Yokohama-shi,
JP) ; Takubo, Chiaki; (Tokyo, JP) |
Correspondence
Address: |
FINNEGAN, HENDERSON, FARABOW, GARRETT & DUNNER
LLP
901 NEW YORK AVENUE, NW
WASHINGTON
DC
20001-4413
US
|
Assignee: |
KABUSHIKI KAISHA TOSHIBA
|
Family ID: |
34737220 |
Appl. No.: |
10/866341 |
Filed: |
June 14, 2004 |
Current U.S.
Class: |
430/330 ;
430/314; 430/319 |
Current CPC
Class: |
H05K 3/102 20130101;
H01L 21/4867 20130101; H05K 2203/1105 20130101; H01L 21/4857
20130101; H05K 2203/0522 20130101 |
Class at
Publication: |
430/330 ;
430/314; 430/319 |
International
Class: |
G03F 007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 13, 2004 |
JP |
P2004-005046 |
Claims
What is claimed is:
1. An electronic component manufacturing apparatus, comprising: a
metal particulate spraying mechanism to spray metal particulates
over a substrate having an insulating pattern formed of
thermosetting resin and attach the metal particulates on said
insulating pattern; a heating mechanism to heat and dissolve said
insulating pattern and fix said metal particulates on said
insulating pattern; and a metal particulate eliminating mechanism
to eliminate the metal particulates attached on the surface of the
substrate excluding said insulating pattern.
2. An electronic component manufacturing apparatus, comprising: a
liquid attaching mechanism to attach liquid, containing a specific
ratio of metal particulates and vaporizing at a specific
temperature, on a substrate having an insulating pattern formed of
thermosetting resin; a heating mechanism to heat said insulating
pattern to which said liquid is attached, vaporize said liquid and
at the same time dissolve said insulating pattern, and fix said
metal particulates on said insulating pattern; and a metal
particulate eliminating mechanism to eliminate the metal
particulates attached on the substrate excluding said insulating
pattern.
3. A method of manufacturing an electronic component, comprising: a
metal particulate spraying step to spray metal particulates over a
substrate having an insulating pattern formed of thermosetting
resin and attach the metal particulates on said insulating pattern;
a heating step to heat and dissolve said insulating pattern and fix
said metal particulates on said insulating pattern; and a metal
particulate eliminating step to eliminate the metal particulates
attached on the surface of the substrate excluding said insulating
pattern.
4. A method of manufacturing an electronic component, comprising: a
dissolving step to heat and dissolve an insulating pattern formed
of thermosetting resin and formed on a substrate; a metal
particulate spraying step to spray metal particulates over said
substrate having the insulating pattern which is dissolved, and
attach the metal particulates on the dissolved insulating pattern;
a curing step to heat and cure said insulating pattern, which has
said metal particulates attached thereon, and fix said metal
particulates on said insulating pattern; and a metal particulate
eliminating step to eliminate the metal particulates attached on
the surface of the substrate excluding said insulating pattern.
5. A method of manufacturing an electronic component, comprising: a
liquid attaching step to attach liquid, containing a specific ratio
of metal particulates and vaporizing at a specific temperature, on
a substrate having an insulating pattern formed of thermosetting
resin; a heating step to heat said insulating pattern to which said
liquid is attached vaporize said liquid and at the same time
dissolve the insulating pattern, and fix said metal particulates on
the insulating pattern; and a metal particulate eliminating step to
eliminate the metal particulates attached on the substrate
excluding said insulating pattern.
6. An electronic component, comprising: a thermosetting resin layer
formed on a substrate with a specific pattern; a metal conductor
layer formed on said thermosetting resin layer; and a metal
particulate layer interposed and buried in a boundary between, and
extending over, said thermosetting resin layer and said metal
conductor layer.
Description
CROSS REFERENCE TO THE INVENTION
[0001] This application is based upon and claims the benefit of
priority from the prior Japanese Patent Application No. 2004-05046
filed on Jan. 13, 2004; the entire contents of which are
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an electronic component
manufacturing apparatus, an electronic component manufacturing
method, and an electronic component.
[0004] 2. Description of the Related Art
[0005] In recent years, electrophotographic methods to form an
electronic circuit pattern on a substrate are developed. In the
electrophotographic method to form an electronic circuit pattern,
an electrostatic latent image of a specific pattern is formed on a
photoreceptor, and insulating resin particles, over the surface of
each of which metal particulates adhere, are electrostatically
attached on the electrostatic latent image to form a visible image,
which is then transferred to the substrate, forming an electronic
circuit pattern.
[0006] With the conventional method of forming an electronic
circuit pattern described above, is formed a resin layer containing
metal particulates, which is insulating resin in which metal
particulates disperse almost evenly. Further, the metal
particulates positioned on the surface of the
metal-particulate-containing resin layer are used as a plating
nucleus, in forming a conductive metal layer by electroless plating
or electrolytic plating.
[0007] However, because of the inclusion of the metal particulates
in the metal-particulate-containing resin layer formed by
dissolving plural particles of the insulating resin particles
attaching metal particulates over the surface thereof, the
adhesiveness of the interface between the contained metal
particulates and the resin affects the material to easily crack
which is a cause of a damage. As a result, the strength of the
resin layer in its entirety becomes insufficient.
[0008] In order to solve the above problem, attained is the present
invention, aiming at providing apparatuses and methods to
manufacture an electronic component capable of forming a wiring
pattern of superior adhesiveness with a substrate, and providing an
electronic component having such an wiring pattern.
SUMMARY OF THE INVENTION
[0009] According to an aspect of the present invention, there is
provided an electronic component manufacturing apparatus,
comprising: a metal particulate spraying mechanism to spray metal
particulates over a substrate having an insulating pattern formed
of thermosetting resin and attach the metal particulates on said
insulating pattern; a heating mechanism to heat and dissolve said
insulating pattern and fix said metal particulates on said
insulating pattern; and a metal particulate eliminating mechanism
to eliminate the metal particulates attached on the surface of the
substrate excluding said insulating pattern.
[0010] Further, according to an aspect of the present invention, is
provided an electronic component manufacturing apparatus,
comprising: a liquid attaching mechanism to attach liquid,
containing a specific ratio of metal particulates and vaporizing at
a specific temperature, on a substrate having an insulating pattern
formed of thermosetting resin; a heating mechanism to heat said
insulating pattern to which said liquid is attached, vaporize said
liquid and at the same time dissolve said insulating pattern, and
fix said metal particulates on said insulating pattern; and a metal
particulate eliminating mechanism to eliminate the metal
particulates attached on the substrate excluding said insulating
pattern.
[0011] Furthermore, according to an aspect of the present
invention, there is provided a method of manufacturing an
electronic component, comprising: a metal particulate spraying step
to spray metal particulates over a substrate having an insulating
pattern formed of thermosetting resin and attach the metal
particulates on said insulating pattern; a heating step to heat and
dissolve said insulating pattern and fix said metal particulates on
said insulating pattern; and a metal particulate eliminating step
to eliminate the metal particulates attached on the surface of the
substrate excluding said insulating pattern.
[0012] Further, according to an aspect of the present invention,
there is provided a method of manufacturing an electronic
component, comprising: a dissolving step to heat and dissolve an
insulating pattern formed of thermosetting resin and formed on a
substrate; a metal particulate spraying step to spray metal
particulates over said substrate having the insulating pattern
which is dissolved, and attach the metal particulates on the
dissolved insulating pattern; a curing step to heat and cure said
insulating pattern, which has said metal particulates attached
thereon, and fix said metal particulates on said insulating
pattern; and a metal particulate eliminating step to eliminate the
metal particulates attached on the surface of the substrate
excluding said insulating pattern.
[0013] Furthermore, according to an aspect of the present
invention, there is provided a method of manufacturing an
electronic component, comprising: a liquid attaching step to attach
liquid, containing a specific ratio of metal particulates and
vaporizing at a specific temperature, on a substrate having an
insulating pattern formed of thermosetting resin; a heating step to
heat said insulating pattern to which said liquid is attached,
vaporize said liquid and at the same time dissolve the insulating
pattern, and fix said metal particulates on the insulating pattern;
and a metal particulate eliminating step to eliminate the metal
particulates attached on the substrate excluding said insulating
pattern.
[0014] Furthermore, according to an aspect of the present
invention, there is provided an electronic component, comprising: a
thermosetting resin layer formed on a substrate with a specific
pattern; a metal conductor layer formed on said thermosetting resin
layer; and a metal particulate layer interposed and buried in a
boundary between, and extending over, said thermosetting resin
layer and said metal conductor layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Whilst the present invention will be described with
reference to the drawings, these drawings are provided only for the
illustrative purpose and, in no respect, are intended to limit the
present invention.
[0016] FIG. 1 is a schematic overview of a configuration of an
electronic component manufacturing apparatus according to an
embodiment of the present invention.
[0017] FIG. 2 is a schematic overview of a configuration of a metal
particulate attaching apparatus according to the embodiment of the
present invention.
[0018] FIG. 3 is a sectional view showing a state of metal
particulates which are attached by using the metal particulate
attaching apparatus according to the embodiment of the present
invention.
[0019] FIGS. 4A AND 4B are another sectional views showing a state
of metal particulates which are attached by using the metal
particulate attaching apparatus according to the embodiment of the
present invention.
[0020] FIG. 5 is a schematic overview of a configuration of another
metal particulate attaching apparatus according to an embodiment of
the present invention.
[0021] FIGS. 6A, 6B, 6C, 6D, and 6E are schematic sectional views
showing an example of a formation step of a monolayer electronic
circuit board according to an embodiment of the present
invention.
[0022] FIGS. 7F, 7G, 7H, 7I, and 7J are schematic sectional views
showing an example of the forming step of the multi-layer
electronic circuit board according to the embodiment of the present
invention.
DESCRIPTION OF THE EMBODIMENTS
[0023] In the following, an embodiment of the present invention
will be described with reference to the drawings.
[0024] FIG. 1 shows an overview of a configuration of an electronic
component manufacturing apparatus 1 according to an embodiment of
the present invention.
[0025] The electronic component manufacturing apparatus 1 according
to the embodiment of the present invention consists mainly of: a
resin pattern forming apparatus 2 to form, on a substrate 16, a
resin pattern serving as an insulating pattern; a metal particulate
attaching apparatus 22 to attach metal particulates 29 on a resin
layer 19 formed on the substrate 16; a heating apparatus 17 to heat
the resin layer 19; a metal particulate eliminating apparatus 20 to
eliminate metal particulates 29 attached on the substrate 16; and
an electroless plating tank 21 to form a metal conductor layer 19,
which has metal particulates 29 attached thereon.
[0026] Here, FIG. 1 shows, as an example of the resin pattern
forming apparatus 2, a resin pattern forming apparatus using an
electrophotograhic method to charge a surface of a photosensitive
drum 10 by a corona charger 11, form a specified latent pattern by
irradiating laser beam over the surface of the photosensitive drum
10 by a laser generating/scanning apparatus 12, make resin
particles 18 electrostatically adsorbed by the latent pattern on
the surface of the photosensitive drum 10, make a visible image
(pattern) formed of resin particles 18 on the surface of the
photosensitive drum 10 contact with, and pressed by, a surface of
an intermediate transfer drum 14 heated by the heating apparatus
15, and transfer the pattern to the substrate using the viscosity
of the resin.
[0027] It should be noted that the resin pattern forming apparatus
2 is not limited to an apparatus using the electrophotographic
method described herein. For example, apparatuses by conventionally
used methods, such as the inkjet method to form a resin pattern by
spraying from a nozzle a resin in paste form, or the screen
printing method to form a resin pattern by using a
pattern-corresponding mask to print a resin in paste form, can be
used.
[0028] In this embodiment, a dry or a wet toner transfer technique
for a known electrophotographic transfer system can be applied to
an imaging apparatus 13 in the resin pattern forming apparatus 2.
When the imaging apparatus 13 is a dry one, it stores resin
particles 18 having the size of 3 to 50 .mu.m. Here, a preferable
size of the resin particle is 8 to 15 .mu.m. On the other hand,
when the imaging apparatus is a wet one, the imaging apparatus 13
stores resin particles 18 having the size not exceeding 3
.mu.m.
[0029] Further, as resin forming the resin particles 18, B-stage
thermosetting resin, which is solid at a room temperature, can be
used. The B stage is a state in which at least a part of the
thermosetting resin is not cured, and provision of a specific heat
dissolves the uncured part. Those usable as the B-stage
thermosetting resin are epoxy resin, polyimide resin, phenolic
resin, and the like, and a charge control agent may be added
thereto, where it is necessary. Further, such particulates as
silica included with a specific ratio may be dispersed within the
resin particle 18, which in particular contributes to the
controlling of characteristics such as stiffness or thermal
expansion coefficient of the multi-layer electronic circuit board.
As a result, the reliability of the board can be enhanced.
[0030] Subsequently, the metal particulate attaching apparatus 22
will be explained with reference to FIGS. 2 to 5.
[0031] FIG. 2 shows a configuration of an embodiment of the metal
particulate attaching apparatus 22. FIGS. 3 to 4 show sectional
views of a state in which the metal particulates 29 are attached by
using the metal particulates attaching apparatus 22. FIG. 5 shows a
configuration of a metal particulate attaching apparatus 35, which
is another example other than the metal particulate attaching
apparatus 22.
[0032] The metal particulate attaching apparatus 22 shown in FIG. 2
is an apparatus to spray the metal particulates 29 over the resin
layer transferred on the substrate 16, and consists mainly of a
blending section 25 and a spray nozzle 26 connected to a lower
surface of the blending section 25.
[0033] The blending section 25 are connected to a compressed air
line 27 to supply a compressed air, and a metal particulate line 28
to supply the metal particulates 29 to the blending section 25.
When the compressed air is supplied to the blending section 25, the
metal particulates 29 disperse almost evenly in the blending
section 25 during the period they are staying in the blending
section 25. The metal particulates 29 are then led to the spray
nozzle 26 which communicates with the blending section 25, and,
with the compressed air, ejected from ejection holes of the spray
nozzle 26 over the resin layer 19.
[0034] The metal particulates 29 ejected over the resin layer 19
are attached on the upper surface of the resin layer 19, as shown
in FIG. 3. Here, the proportion of a surface coverage ratio
indicating the area of the resin layer 19 covered by the metal
particulates 29 to the area of the upper surface of the resin layer
19 is preferred to be 10 to 100%. A surface coverage ratio of less
than 10% may result in insufficient precipitation of the plating. A
more preferable surface cover age ratio is 50 to 80%. Incidentally,
the metal particulates 29 ejected over the resin layer 19 can be
attached not only on the upper surface of the resin layer 19, but
it is also possible to attach the metal particulates 29 on a side
surface of the resin layer 19.
[0035] Subsequently, the substrate 16 is led to and heated by the
heating apparatus 17 and cure the resin layer 19, and the metal
particulates 29 are fixed on the upper surface of the resin layer
19. Here, a part of the metal particulates 29 fixed on the upper
surface of the resin layer 19 are not buried into the resin layer
19, but projects externally on the upper surface of the resin layer
19. These externally projecting metal particulates 29 become a
plating nucleus for an electroless plating, allowing forming of a
metal conductor layer having favorable conductive properties.
[0036] The volumes of the compressed air and the metal particulates
29 supplied to the blending section 25 can be regulated by, for
example, providing regulating valves (not shown) or the like to a
compressed air line 27 and a metal particulate line 28. It is noted
that while a working fluid herein used for dispersing the metal
particulates 29 is air, this is not a limitation, and for example,
inert gas such as nitrogen can be used. Here, the temperature of
the working fluid may be controlled so as to dissolve and keep the
viscosity of the surface of the resin pattern.
[0037] As the metal particulate 29, a metal particulate formed at
least one of the group of platinum (Pt), palladium (Pd), copper
(Cu), gold (Au), nickel (Ni), and silver (Ag) is preferably used.
Such metal particulates 29 become a nucleus of the electroless
plating which will be described later, and play a catalytic role in
the plating step. In the group, palladium (Pt) is in particular
preferable for use. Further, the average particle size of the metal
particulate 29 is preferable within 5 nm to 1000 nm, and more
preferable within 5 nm to 500 nm. This is because smaller average
particle size of the metal particulates 29 permit high
dispersibility.
[0038] The above-described method of ejecting the metal
particulates 29 over the resin layer 19 by the compressed air and
attaching the metal particulates 29 on the upper surface of the
resin layer 19 is suitable when the size of the metal particulates
29 to be used is relatively large within its average particle size
of 5 nm to 1000 nm.
[0039] Specifically, when the average particle size of the metal
particulates 29 to be used is small, a liquid in which the metal
particulates are dispersed can be used, the solvent medium of
which, for example, is formed of aromatic solvent such as toluene,
xylene, mineral spirit, and isoparaffin, and a liquid of relatively
low boiling point such as water and spirits. A state of the resin
layer 19 in the case of using liquid is shown in FIG. 4A. For the
liquid 30, is suitable a liquid which vaporizes at the temperature
at which the resin to be used is cured (for example, 150.degree. C.
to 200.degree. C.) or at a lower temperature thereof.
[0040] In the case of using the liquid 30 as a working fluid, in
the liquid 30 the metal particulates may be dispersed in the
solvent in advance, or a stirrer may be provided within the
blending section 25, to stir the metal particulates 29 and the
liquid 30 so that the metal particulates 29 are dispersed evenly in
the liquid 30.
[0041] Here, the ratio of the metal particulates 29 included in the
liquid 30 is preferably within 1 to 50% by weight. When the ratio
of the metal particulates 29 included in the liquid 30 is less than
1% by weight, the function of the metal particulates 29 fixed on
the resin layer as a plating nucleus may deteriorate. On the other
hand, when the ratio of the metal particulates 29 included in the
liquid 30 is larger than 50% by weight, it becomes difficult to
spray the liquid 30 evenly from the spray nozzle 26. Additionally,
a more preferable ratio of the metal particulates 29 included in
the liquid 30 is within 1 to 20% by weight.
[0042] Subsequently, a pressurizer to pressurize the inside of the
blending section 25 is provided, and the liquid 30 containing the
metal particulates 29 is sprayed over the resin layer 19 from the
spray nozzle 26. The metal particulates 29 sprayed over the resin
layer 19 adhere on the upper surface of the resin layer 19 together
with the liquid 30, as shown in FIG. 4A. Incidentally, the
pressurizer may include an electromagnetic pump interposed between
the spray nozzle 26 and the blending section 25. Further, for the
spray nozzle 26, it is preferable to use an atomizing nozzle such
as a pressure spraying valve or an air-spraying valve.
[0043] Instead of spraying liquid 30 including the metal
particulates 29 from the spray nozzle 26, the liquid 30 may be
coated over the resin layer 19 as liquid column. In such a case,
the liquid 30 is flown out by its own weight, without a
pressurizier. Here, the spray nozzle 26 to be used may be, for
example, a barrel unit such as a pipe, but it is not a limitation,
and anything allowing coating of the liquid 30 over the resin layer
19 as liquid column may be used.
[0044] Subsequently, the substrate 16 is led to, for example, the
heating apparatus 17, and the liquid 30 vaporizes by heating. When
the liquid 30 vaporizes, the metal particulates 29 adhere on the
upper surface of the resin layer 19. Heated by the heating
apparatus 17, the resin layer 19 dissolves, and is cured, so that
the metal particulates 29 are fixed on the upper surface of the
resin layer 19, as shown in FIG. 4B. Here, a part of the metal
particulates 29 fixed on the upper surface of the resin layer 19
are not buried into the resin layer 19, but projecting externally
on the upper surface of the resin layer 19. The externally
projecting metal particulates 29 become a plating nucleus for the
electroless plating, allowing forming of the metal conductor layer
having favorable conductive properties.
[0045] Here, the curing of the resin layer 19 and the vaporizing of
the liquid 30 are simultaneously carried out by the heating
apparatus 17, but the liquid 30 can be vaporized before leading the
substrate 16 to the heating apparatus 17, by separately providing a
vaporizer to vaporize the liquid 30.
[0046] Further, other than spraying over the resin layer 19 the
liquid 30 by including the metal particulates 29, a metal
particulate attaching apparatus 35 shown in FIG. 5, can be used to
attach the metal particulates 29 on the rein layer 19.
[0047] This metal particulate attaching apparatus 35 includes an
accommodating container 31 to accommodate the substrate 16, and a
liquid 32 containing the metal particulates 29 stored in the
accommodating container 31.
[0048] The liquid 32 stored in the accommodating container 31 is
formed of the same liquid as the liquid 30 used as the working
fluid described above. For example, aromatic solvent such as
toluene, xylene, mineral spirit, and isoparaffin, and a liquid of
relatively low boiling point such as water and spirits can be used
as the liquid 32. For the liquid 32, suitable is a liquid which
vaporizes at the temperature at which the resin to be used is cured
(for example, 150.degree. C. to 200.degree. C.) or at a lower
temperature thereof.
[0049] A preferred ratio of the metal particulates 29 included in
the liquid 32 is within the range of 1 to 5o% by weight. If the
ratio of the metal particulates 29 included in the liquid 32 is
less than 1%, the plating precipitation may become insufficient. On
the other hand, if the ratio of the metal particulates 29 included
in the liquid 32 is more than 50% by weight, the metal particulates
29 may not adhere on the resin layer 19 at the intended ratio of
surface coverage. Further, a more preferable ratio of the metal
particulates 29 included in the liquid 32 is 1 to 20% by
weight.
[0050] The substrate 16, to which the resin layer 19 is
transferred, is dipped for a certain period of time in the
accommodating container 31 storing the liquid 32, and picked out.
On the surface of the substrate 16 and the resin layer 19, the
liquid 32 containing the metal particulates 29 adheres, as shown in
FIG. 4A.
[0051] Subsequently, the substrate 16 is led to, for example, the
heating apparatus 17, and heated such that the liquid 32 vaporizes.
When the liquid 32 vaporizes, the metal particulates 29 adhere on
the upper surface of the resin layer 19. Further, heated by the
heating apparatus 17, the resin layer 19 dissolves, and is then
cured, so that the metal particulates 29 adhere on the upper
surface of the resin layer 19, as shown in FIG. 4B. Here, a part of
the metal particulates 29 fixed on the upper surface of the metal
layer 19 project over the upper surface of the resin 19, without
being buried into the resin layer 19. These metal particulates 29
projecting externally become a plating nucleus for the electroless
plating, allowing forming of the metal conductor layer having
favorable conductive properties.
[0052] In the case hereof, the curing of the resin layer 19 and the
vaporizing of the liquid 32 are simultaneously carried out by the
heating apparatus 17, but it is also possible to separately provide
a vaporizer to vaporize the liquid 32 so that the liquid 32
vaporizes before the substrate 16 is led to the heating apparatus
17.
[0053] Here, a tensile strength test is performed to evaluate the
adhesiveness between the resin layer and the substrate, in which
are compared the substrate having the resin layer 19 attaching the
metal particulates 29 on its upper surface, and the substrate
having the resin layer containing the metal particulates 29
dispersed almost evenly. The ratio of the metal particulates in the
resin layer containing the metal particulates is 50% by weight.
[0054] The tensile strength measurement result is 50 MPa for the
substrate having the resin layer which fixes the metal particulates
29 on the surface thereof, and 20 MPa for the substrate having the
metal-particulate-including resin layer. This measurement results
indicate that with the resin layer 19 having the metal particulates
29 fixed on the upper surface thereof, the strength of the resin
layer, more specifically, the strength of the adhesive layer itself
between the conductor layer and the substrate, becomes high,
because it is only on the upper surface of the resin layer 19 that
the metal particulates 29 are fixed. As a result, a wiring pattern
with a high adhesiveness with the substrate and a sustained
mechanical strength can be formed.
[0055] Next, an example of operations of an electronics component
manufacturing apparatus 1 will be explained.
[0056] The substrate 16 to which the resin layer 19 is transferred
by the resin pattern forming apparatus 2 is led to the metal
particulate attaching apparatus 22. The metal particulates are
attached on the upper surface of the resin layer 19 of the
substrate 16 having led to the metal particulate attaching
apparatus 22.
[0057] Subsequently, the substrate 16 having the resin layer 19
attaching the metal particulates 29 on the upper surface thereof is
led to the heating apparatus 17, and the resin layer 19 at the B
stage having transferred to the substrate 16 is cured by heating or
light irradiating. Here, the metal particulates 29 adhering over
the resin layer 19 is fixed over the resin layer 19 by the curing
of the rein layer.
[0058] Subsequently, the substrate 16 is led to the metal
particulate eliminating apparatus 20, where the metal particulates
29 adhering on the substrate 16 are eliminated, excluding the resin
layer. In the metal particulate eliminating apparatus 20, the metal
particulates 29 are eliminated by, for example, shot blast, air
blast, ultrasonic cleaning, or the like.
[0059] The substrate 16, the metal particulates 29 adhering on
which are eliminated excluding the resin layer 19, is led to an
electroless plating tank 21 for copper, where copper is
specifically precipitated, with the metal particulates 29 as the
plating nucleus. As a result, a conductor pattern having a
favorable conductivity can be formed. It is noted that while herein
presented is a plating apparatus composed only of the electroless
plating tank 21, this is not a limited way, and both the
electroless plating and electrolytic plating can be carried
out.
[0060] After the plating, it is preferable to completely cure the
resin layer 19 by reheating or irradiating with the heating
apparatus 17, such that the substrate 16 and the resin layer 19
further adhere to each other and any removal or the like can be
prevented. The thickness of the resin layer 19 when it is
completely cured is 0.5 .mu.m to 15 .mu.m.
[0061] It is noted that, in the case where the metal particulates
29 are sprayed over the resin layer 19 using air or the like in the
metal particulates attaching apparatus 22, the resin layer 19
having high viscosity is preferred, such as the one formed on the
substrate 16 herein described. For example, before led to the metal
particulate attaching apparatus 22, the resin layer 19 formed on
the substrate 16 is preferably heated in advance, so that the resin
layer 19 becomes viscid. In that case, for example, a heating
apparatus is provided before the entry of the resin layer 19 to the
metal particulate attaching apparatus 22, which allows the metal
particulates to adhere on the rein layer 19 appropriately. Further,
when an inkjet method or a screen printing method is employed to
the resin pattern forming apparatus 2, the metal particulates can
be attached using the adhesiveness of the resin layer 19 over the
substrate 16.
[0062] In addition, the electroless plating is carried out over the
resin layer 19 after fixing the conductive metal particulates 29
which are the plating nucleus for the electroless plating, in the
manner that a part of which project over the upper surface of the
resin layer 19, so that a metal conductor layer having a favorable
conductivity can be formed.
[0063] Further, a flexible multi-layer electronic circuit board can
be manufactured in the manner that a board or a sheet formed of
PTFE resin is used as a substrate to form an insulating pattern and
a conductor pattern alternatively, and the multi-layer circuit
wiring part so formed is peeled off from the substrate.
[0064] Furthermore, an electronic circuit board manufactured as a
substrate by a conventional method (for example, a subtractive
board) may be used, on which a conductor pattern is formed by the
above-described forming method. When manufacturing a substrate, to
which heat-resistance is not required, thermoplastic resin such as
an acrylic resin can be used instead of the thermosetting resin
which is processed up to the B stage.
[0065] (An example of a configuration and formation step of a
monolayer electronic circuit board or a multi-layer electronic
circuit board)
[0066] First, an example of a formation step of a monolayer
electronic circuit board will be explained with reference to FIGS.
6A to 6E. Subsequently, an example of a formation step of a
multi-layer electronic circuit board by forming another electronic
circuit on the monolayer electronic circuit board will be explained
with reference to FIGS. 7f to 7J.
[0067] FIGS. 6A, 6B, 6C, 6D, and 6E are sectional views showing the
formation steps of the monolayer electronic board. FIGS. 7F, 7G,
7H, 7I and 7J are sectional views showing the formation steps of
the multi-layer electronic board, following the formation steps of
the monolayer electronic circuit board shown in FIGS. 6A to 6E. It
is noted that the following examples of the formation steps of the
monolayer electronic circuit board and the multi-layer electronic
circuit board are carried out based on the above-described
operational example of the electronic circuit manufacturing
apparatus 1, and explanations on the overlapping operations will be
omitted.
[0068] First, the formation step of the monolayer electronic
circuit board shown in FIGS. 6A to 6E will be explained.
[0069] Over a substrate 71, a resin layer 72 is formed with a
predetermined conductor pattern (FIG. 6A), and on the upper surface
of the resin layer 72, metal particulates are attached, so as to
form a metal particulate layer 72 (FIG. 6B).
[0070] Subsequently, the upper surface of the resin layer 72 having
the metal particulate layer 73 fixed thereover is electrolessly
plated, so as to form a conductive metal layer 74 formed of a layer
of plating by copper or the like (FIG. 6C).
[0071] A resin layer 75 is then formed on the metal particulate
layer excluding a part for forming a via layer 76 on the conductive
metal layer 74, and on the substrate 71 (FIG. 6D).
[0072] A via layer 76 is then formed by electrolessly plating the
recess for forming the via layer 76 on the conductive metal layer
74 (FIG. 6E). With the above process, a monolayer electronic
circuit board is formed.
[0073] Next, a step to form a multi-layer electronic board by
forming another electronic circuit on the monolayer electronic
circuit board will be explained, with reference to FIGS. 7F, 7G,
7H, 7I, and 7J.
[0074] In order to form a second layer on the monolayer electronic
circuit board formed by the monolayer electronic circuit board
forming step, a resin layer 77 is formed with a predetermined
pattern, on an area which extends over a part of the via layer 76,
and on the resin layer 75 (FIG. 7F).
[0075] Metal particulates are then fixed on the upper surface of
the resin layer 77, so as to form a metal particulate layer 78
(FIG. 7G).
[0076] Electroless plating is then carried out over the surface of
the via layer 76 and on the upper surface of the resin layer 77
having the metal particulate layer 78 fixed thereon, so as to form
a conductive metal layer 79 formed of a layer of plating by copper
or the like (FIG. 7H).
[0077] A resin layer 80 is then formed on the conductive metal
layer 79 excluding a part for forming a via layer 81, and on the
resin layer 75 (FIG. 7I).
[0078] A via layer 81 is then formed by electrolessly plating the
recess for forming the via layer 81 on the conductive metal layer
79 (FIG. 7J).
[0079] Thereafter, the steps shown in FIG. 7F and thereon are
repeated such that a multi-layer electronic circuit board composed
of a plurality of layers can be formed.
[0080] Further, on the monolayer electronic circuit board and the
multi-layer electronic circuit board, a metal particulate layer is
formed, in which at least a part of the conductive metal
particulates are projecting over the surface of the resin layer
forming a conductor pattern, so that plating can be carried out
with the projecting metal particulates as the plating nucleus. This
permits the metal particulates to serve as catalyst in the progress
of the plating, so that an electronic circuit board can be obtained
in which a conductive metal layer of a favorable state is
appropriately formed on the resin layer forming the conductor
pattern. After the conductor pattern is plated, the metal
particulates lie in the boundary portion between the resin layer
and the conductive metal layer extending over respective
layers.
[0081] According to the one embodiment of the present invention
described above, a part of the metal particulates projecting and
serving as the plating nucleus can be evenly fixed on the surface
of the resin layer. This allows an optimal plating, so that a
conductive metal layer of a favorable state can be formed.
[0082] Further, according the one embodiment of the present
invention, the resin layer of the conductor pattern forms an
insulating resin layer without having metal particulates included
in, or attached on the surface of, each of resin particles, and
thereafter has the metal particulates fixed thereon, so that a
toner (resin particles 18) of a desired size, weight, quantity of
electric charges, can be easily fabricated.
[0083] Furthermore, the resin layer for forming the conductor
pattern has metal particulates fixed only on the surface thereof,
so that a wiring pattern having high cohesiveness between the
conductor layer and the substrate and a sustained mechanical
strength can be formed.
[0084] It is to be understood that the present invention is not
limited to the specific aspects described herein with reference to
the drawings, and includes all variations thereto insofar as they
are included in the range claimed in the following.
* * * * *